Mourinho: We were waiting for Costa

Chelsea boss Jose Mourinho has called new striker Diego Costa a bargain, saying this is "the player we were waiting for" to drive them towards the Premier League title.

Returning to Stamford Bridge for the first time since helping Atletico Madrid oust Chelsea in the Champions League semi-finals, Costa impressed both the fans and his manager by scoring twice inside eight minutes in a 2-0 win against Real Sociedad.

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"Should this new-look squad reach its potential, there is every chance that Chelsea will win their fifth Premier League title and that Jose Mourinho will once more enshrine his reputation as the 'Special One'"

Mourinho heaped praise on his new striker, saying that the Spain international can help Chelsea improve in multiple areas as they strive to win their first Premier League title since 2010.

"What can we expect? I expect Diego. And Diego is a team player who works hard, he's not just about goals," Mourinho said. "It's about his defensive work, mentality and ambition.

"This is the player we bought and we were waiting for since last season. This is why we didn't buy a striker in the winter market. We were waiting for him, we have him and hopefully everything goes well.

"He looks adapted to the team, and the Premier League, not just Chelsea, should be happy. Sometimes we lose important players going to other countries and sometimes we bring new top players here."

Chelsea paid £32 million to bring Costa over from Atletico, but Mourinho insisted that was a "bargain" for a player of his quality.

"You can consider that [a bargain] because the market is crazy and the values are very high," Mourinho said. "For a striker like him, a champion in Spain, a Champions League finalist, a 25-year-old, we consider the price was very much in our favour."

Mourinho gloated about his other transfer coups this summer as well, saying he was pleased to add Filipe Luis and Cesc Fabregas in their primes.

"We bought three players, in Filipe, Diego and Cesc, at the best stage for a player, between 25 and 30," Mourinho said. "They are three experienced players with qualities to immediately improve our team. Last season we went to a different profile when we bought people like [Mohamed] Salah and [Andre] Schurrle who needed time. Obviously we also went for [Kurt] Zouma but the strong nucleus of Filipe, Diego and Cesc is ready.

"The squad has improved for sure. This is the Premier League, every team tries to be better. Are we ready for that? Yes, but this is England. In some countries only two teams can win the league, sometimes only one, but here it's five or six.

"The only thing I can say is that I very much like the squad. The club were fantastic because they gave me the three targets I asked for. We have the squad we want to have, it's a squad for tomorrow, for next season and also with big possibilities for the next five to 10 years."

Mourinho also revealed that Didier Drogba, another option for Chelsea's frontline, could recover from an ankle injury in time to be in the squad for Monday's Premier League opener against Burnley.

"He's good," Mourinho said of the Ivorian. "I don't want to say ready for Monday but with the quality of our medical department and the mentality he has, I'm not saying it's impossible for him to recover for Monday."

On the other end of the pitch, Mourinho gave goalkeeper Thibaut Courtois 90 minutes in goal for the first time in a Chelsea shirt on Tuesday, but said a decision on who to start against Burnley will not be made until the day before the match.

"I played Thibaut for 90 minutes because he was injured and didn't play last weekend," Mourinho said. "Petr [Cech] played two matches in Turkey and the first half against Ferencvaros. Since he arrived Courtois has only played 45 minutes against Werder Bremen, he needs to play.

"The fact Courtois played 90 minutes wasn't me saying he's first choice for Monday, it's because he didn't play the last three matches. The players don't know [who's first choice]. When will I tell them? On Sunday."

After enduring a tricky start to his Manchester United career, perhaps it is fair that Marcos Rojo celebrated so boisterously as he watched his first professional club Estudiantes beat fierce rivals Gimnasia